Direct answer
Polyurea is chosen when rapid cure, seamless high build, and specific chemical resistance align with the asset (tank, pool shell, industrial containment). Polyurethane waterproofing coatings are chosen when layered terrace systems, adjustable thickness, and compatible topcoats for UV match the exposure schedule.
Petroseal supplies both; the swimming pool application page links pool system build-ups. Do not specify polyurea on a simple exposed roof cap without UV and maintenance review—APP membrane may remain the correct primary plane.
Selection table
| Requirement | Typical choice | Petroseal reference |
|---|---|---|
| Swimming pool shell / tank lining | Polyurea system when spec allows | /systems/swimming-pool-waterproofing |
| Industrial bund, fast turnaround | Polyurea | /systems/polyurea-waterproofing |
| Terrace, pedestrian roof | Polyurethane multi-coat | /systems/polyurethane-waterproofing |
| Large flat roof, UV cap | APP membrane | /systems/app-waterproofing |
| Complex details only | Liquid at details + sheet field | Combined method statement |
Application discipline
Both technologies fail from moisture in concrete, wrong mix ratio, and missing DFT checks. Trained applicators and manufacturer method statements matter more than brand slogans from any Lahore contractor. Petroseal download pages list available TDS/brochures; method statements are flagged where still pending on the tech-centre gaps list.